Until 2005, no scientist had ever photographed a living giant squid. One hadn’t been filmed until 2013. But scientists believe there are millions of them out there.

In June, a NOAA Office of Ocean Exploration and Research expedition captured the first footage of a giant squid in American waters.

The New Yorker’s David Grann wrote that giant squid can be „larger than a whale and stronger than an elephant, with a beak that can sever steel cables.“

Here’s what is known about the mysterious beast, and why so much is still not known.

Why giant squid, the once mythical kraken of the deep, are still mystifying scientists 150 years after they were discovered slides

Why giant squid, the once mythical kraken of the deep, are still mystifying scientists 150 years after they were discovered slides

Living 1,300 to 3,000 feet down in the ocean, giant squid inhabit the deepest, darkest places in the world. No one knows for sure how long they live for, how they find partners, how they migrate, where they lay their eggs, or even if they make any sounds. To put it bluntly, the giant squid remains a mystery.

Genetics show they've been around for about 730,000 years. They've been in human legends for hundreds of years. Giant squid are the inspiration for the "Kraken" in Norse mythology, and the beasts in Jules Verne's book "20,000 Leagues Under the Sea."

One particularly good story was written in "The Natural History of Norway" in 1755, which described the giant squid as being as large as "a number of small islands," and when the giant squid began to sink, it caused whirlpools that sucked everyone down with it.

Until about 150 years ago, most people didn't think they were real. They were sea monsters made up by sailors. But their existence started to become more plausible. One factor was finding sucker scars, like burn marks all over sperm whales, their main predator. Their beaks have also been found in the whales' stomachs. These were signs of the deep sea battles waged between whale and squid.

In 1857, Japetus Steenstrup, a Danish zoologist at the University of Copenhagen, introduced the giant squid into the scientific community. After studying a beak that washed up in Denmark, he published his research and confirmed to the world the giant squid was in fact real. He named them Architeuthis Dux, which is Latin for "ruling squid."

In 1873, three fisherman in Conception Bay, Newfoundland, came upon a giant squid that tried to sink their boat. They fought it off, and the squid escaped after releasing dark clouds of ink. But the fishermen managed to secure 19 feet of tentacle — more proof of the mythic squid's existence.

In 1997, US National Geographic tried to use sperm whales to study the giant squid. They attached video cameras, hoping to see the whale eating the squid. But they weren't successful.

Despite Streenstrup's early success, few people have been able to make a career out of studying giant squid alone, again because they appear so rarely. For marine ecologist Angel Guerra, who here is dissecting a giant squid, it's like a "hobby."

New Zealand marine biologist Steve O'Shea, whom The New Yorker dubbed "The Squid Hunter," was for a time one of the most well-known giant squid scientists. His quest began in 1996, and ended in 2011.

Asked why he kept going for so long, he told Business Insider he made a vow after a failed attempt to chronicle the life of giant squid from being a juvenile, onwards.

„At the end of it all, camera thrown in my face, tears streaming, dreams destroyed, lifeless corpses of juvenile giant squid in the palm of my hand, I recall vowing to continue my insane quest until I achieved what I’d set out to do, or someone else did,“ he said.

Wikimedia

One of O'Shea's goals had been to unveil giant squid to the public in an aquarium. He wanted everyone, not just scientists and fishermen, to experience "the majesty of these animals" up close and personal, rather than watching a fleeting, grainy image on a television screen.

Ian Nicholson / PA images / Getty

In 2003, O'Shea led a team trying to document the giant squid as they migrated into New Zealand waters. His plan was to grind up squid sex organs and squirt them into the water to get squids to mate with the camera lens.

He told BBC, „The freezer bag at home — to my wife’s disgust — is actually full of giant squid gonad samples. We’re going to grind all of this up, and we’re going to have this puree coming out from the camera, squirting into the water.“

He said „the dream“ was to get „sensational footage of the giant squid trying to do „obscene things“ with the camera. The experiment failed.

Fernando Camino / Cover / Getty

Then, on September 30, 2004, the giant squid became a little less mythic. Marine biologists Tsunemi Kubodera and Kyoichi Mori took the first-ever photo of a living giant squid off the coast of Japan's Chichijima Island, where sperm whales were recorded with suction marks.

They lowered a hook with a camera and bait down 3,000 feet. A giant squid attacked, and used its tentacles to envelop the bait, like a python envelopes its prey. After four hours of trying to free its tentacles, it died.

Tsunemi said the incident changed the perception of giant squid being a laid-back, deep-sea drifter, and gave way to an image of a quick and agile predator of the deep.

Tsunemi was on a roll. In 2006, his team published the first video of a live giant squid. It was relatively small, at 110 pounds and 11 feet long, but it was the first moving pictures of the creature. "Nobody has ever seen a live giant squid except fishermen," he told Reuters.

In 2007, a 6.5-foot long, 550-pound giant squid washed up in Tasmania. With its tentacles it measured 26 feet — the same length as a bus. Tasmanian Museum curator David Pemberton said it was one of the biggest ever discovered. The squid was thought to be feeding on grenadier fish in Australia's cold winter waters.

In 2012, the giant squid was recorded in its natural habitat for the first time. The trick to it was using a camera, designed by marine biologist Edith Widder, which emitted a blue light, like the light produced by a type of jellyfish known as Atolla. The squid they caught on camera wrapped itself around the camera, and confirmed to the scientists that it was a predator.

Widder told the BBC there were probably millions in the oceans, since they kept so many sperm whales fed. It's because humans scared them off that more hadn't been seen. So, knowing this, she designed a camera without thrusters or a motor. The only illumination was red light that's invisible to deep-sea animals, because they have adapted to primarily seeing blue.

O'Shea was on board for the momentous occasion. "This proved to be the last time I would be in front of the camera chasing this infernal animal," he said. "When Ku achieved the end game, securing the most stunning imagery of the animal alive, there was no further need for folk like me or my dreams."

Discovery Channel

More evidence was gathered in 2016, when a young female giant squid weighing 231 pounds washed up dead on the Bares peninsula in Spain. Its death pointed to the possibility that giant squid kill each other for food piracy.

In northern Spain waters, giant squid feed on fish called blue whiting, which swim near the surface. The giant squid has to ascend to the surface to catch them. Scientists thought what might have happened was that a second squid might have attacked it on its return to the deep, and stole its food.

After the altercation, scientists thought it could have floated back up to warmer water, which decreases blood flow in squid, and causes something close to asphyxiation. In such a state, it wouldn’t have been able to fight the current, which dragged it to shore.

Alonso Gonzalez / Reuters

In June 2019, about 100 miles southwest of New Orleans in the Gulf of Mexico, the first giant squid was caught on camera in American waters. Nathan Robinson, who headed the team, found the clip after reviewing 20 hours hours of footage. "My heart felt like exploding," he told The New York Times.

The discovery was important, because the giant squid was filmed not far from one of the largest deepwater oil rigs in the world. Sönke Johnsen, a Duke University biology professor, told The Times it dispelled the notion of a monster lurking in remote waters.

For now, the largest recorded giant squid measured up to 43 feet. Their cousin, the colossal squid, can grow up to 45 feet long, but scientists think giant squid can grow up to 66 feet.

Both colossal and giant squid have the largest eyes on the planet, up to 12 inches wide — as big as a basketball. Scientists think it's because they're necessary to see clouds of bioluminescence, which let them know when a sperm whale is approaching.

Their sharp beak in the center of their arms slices its prey into little pieces, which are then ground down by a tongue-like organ covered in teeth. When the giant squid was filmed in 2014, it didn't shred the bait, as expected, but took small bites, slowly consuming the shrimp, so it didn't choke.

Giant squid have eight arms, and use two long tentacles to seize their prey. But their tentacles don't have any muscle to constrict prey. So if it comes face to face with a sperm whale, its only option is to flee.

Clyde Roper, a retired giant squid hunter, told the BBC that if an animal was snared by enough of the suction cups, then it would be impossible to escape.

American explorer and underwater filmmaker Scott Cassell told Business Insider that giant squid should be considered an "indicator species," since they don't live long, and they're prolific, occupying every ocean.

Scott Cassell.

"They can offer valuable clues to oceanic health, both in distribution of species they rely on as food and for species that rely on them as food. In a way they're the center-point species," he said. "Sadly, the open sea is a terrible business partner and there is little pay-off for saving our oceans, and huge profits in killing it, overfishing, mining, shipping, and it seems that paradigm won't change anytime soon."

NOAA OER/Journey into Midnight/Photo by Danté Fenolio

But much about the giant squid still remains unknown, and because of warming waters and oceans becoming more acidic, the species could die out without humans ever knowing.